In the study, researchers measured the verbal and mathematic skill of 660 participants, along with analyzing their cognitive style (intuitive vs. analytical). Participants’ smartphone habits were also reviewed. Scientists found that intuitive thinkers — that is, those who think an act more based on instinct and gut feeling — used their smartphone's search engine more often to answer questions and solve problems. Researchers suggest this means smartphones are making intuitive thinkers even lazier, as they are using phones as extensions of their own mind.

“They may look up information that they actually know or could easily learn, but are unwilling to make the effort to actually think about,” says study co-author Gordon Pennycook, a PhD candidate at the Department of Psychology at Waterloo. This increased reliance of smartphones could have an especially negative impact on the aging brain, the study warns. Researchers stop short of suggesting that smartphones actually decrease intelligence, however.